<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    
    <div id="app">
        <ul>
            <li v-for="(k,v) in arr" :key="v">{{k}} <button @click=" arr.splice(arr.findIndex(e=>e === k),1)">删除</button></li>
        </ul>
        <button @click="add">走一走</button>
    </div>

    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>

    <script>
        new Vue({
            data:{
                arr:[]
            },
            methods:{
                add(){
                    let randomNum = Math.floor(Math.random() * 20) + 1
                    this.arr.push(randomNum)
                }
            }
        }).$mount('#app')
    </script>


</body>
</html>